US3507189A - Air-over-liquid hydraulic system - Google Patents

Air-over-liquid hydraulic system Download PDF

Info

Publication number
US3507189A
US3507189A US726310A US3507189DA US3507189A US 3507189 A US3507189 A US 3507189A US 726310 A US726310 A US 726310A US 3507189D A US3507189D A US 3507189DA US 3507189 A US3507189 A US 3507189A
Authority
US
United States
Prior art keywords
liquid
motor
air
fluid
tank
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US726310A
Inventor
Donald E Beckett
William N Beckett
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BECKETT HARCUM CO
Original Assignee
BECKETT HARCUM CO
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BECKETT HARCUM CO filed Critical BECKETT HARCUM CO
Application granted granted Critical
Publication of US3507189A publication Critical patent/US3507189A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/06Servomotor systems without provision for follow-up action; Circuits therefor involving features specific to the use of a compressible medium, e.g. air, steam
    • F15B11/072Combined pneumatic-hydraulic systems
    • F15B11/0725Combined pneumatic-hydraulic systems with the driving energy being derived from a pneumatic system, a subsequent hydraulic system displacing or controlling the output element
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/216Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being pneumatic-to-hydraulic converters
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/405Flow control characterised by the type of flow control means or valve
    • F15B2211/40507Flow control characterised by the type of flow control means or valve with constant throttles or orifices
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/405Flow control characterised by the type of flow control means or valve
    • F15B2211/40515Flow control characterised by the type of flow control means or valve with variable throttles or orifices
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/45Control of bleed-off flow, e.g. control of bypass flow to the return line
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/455Control of flow in the feed line, i.e. meter-in control
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/40Flow control
    • F15B2211/47Flow control in one direction only
    • F15B2211/476Flow control in one direction only the flow in the reverse direction being blocked
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051Linear output members
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/75Control of speed of the output member
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/80Other types of control related to particular problems or conditions
    • F15B2211/885Control specific to the type of fluid, e.g. specific to magnetorheological fluid

Definitions

  • the present invention relates to an air-over-liquid hydraulic system for enhancing the operation of fluid motors of various types, for example double-acting and S111- gle-acting hydraulic cylinders, rotary motors, and the like.
  • An object of the present invention is to greatly enhance the accuracy of control for hydraulic motors.
  • Another object of the invention is to provide an improved hydraulic system for the accurate control of fluid motors, which involves simple and inexpensive reliable equipment that requires a minimum amount of care and servicing.
  • Another object is to provide a hydraulic system possessing the advantages stated, which may be used with safety and great convenience under various conditions of industrial application.
  • the drawing is a diagram of the improved hydraulic system and showing diagrammatically the various components or elements comprising the improved system.
  • a hydraulic motor comprising a cylinder in which is reciprocable a piston 6 having a piston rod 8 extending through one end wall of the cylinder.
  • the piston rod is packed at 10 to avoid leakage of fluid from the cylinder about the rod.
  • the cylinder is provided with major ports 12 and 14 near opposite ends thereof, through which a fluid may be fed to and exhausted from the piston chamber for driving the piston in opposite directions.
  • hydraulic motor 4 may be one of any known type, including single-acting, double-acting, and rotary types of motors. The by way of example in explaining the invention with clarity and simplicity.
  • a pair of upstanding tanks or reservoirs adapted to contain a liquid upon which air or another gaseous medium is superposed, the liquid being designated L.
  • a port 20 which by means of a pipe 23 is placed in fluid communication with motor port 12.
  • a port 22 of tank 18 is connected by means of a pipe 24, with the port 26 of a valve 28.
  • a valving member 30 of valve 28 may be shifted to establish either a connection or a shut-off between port 26 and a pipe 32.
  • Pipe 32 connects with the motor port 14.
  • a shunt pipe 34 may be included in the system to bypass liquid between pipes 34 and 32, Whenever valve 30 is closed.
  • Installed in pipe 34 is a one-way metering valve 36, preferably though not necessarily of the adjustable orifice type, which permits flow of liquid only as the cylinder exhausts through port 14. Accordingly, if pressured liquid is fed into the cylinder through port 12, piston 6 will be moved to displace liquid through port 14 and valve 36 at a predetermined rate of flow.
  • liquid under pressure passing from tank 18 through pipe 24 and valve 30 may pass unrestrictedly to and through motor port 14 to rapid-traverse the piston in the direction of port 12.
  • piping and valving system shown is exemplary only, and may be altered to suit the requirements of any given motor control problem.
  • the metering of fluid in both directions through the motor may be accomplished, if desired, by altering the system in accordance with accepted practices in the art, and various other alterations may be resorted to for adapting the system to different applications or problems encountered.
  • the liquid L fills the motor 4, and partially fills the tanks 16 and 18, so that displacement of liquid from one tank to the other drives the piston 6.
  • air or other gas under pressure may be fed alternatively onto the column of liquid in either tank, through top ports 38 and 40 and pipes 42 and 44.
  • a distribution valve 46 of suitable design is operative to direct air pressure from a source 48 to either of the tanks selectively.
  • the other tank exhauss air from the upper region thereof as will be understoo
  • control valve 46 will be coordinated with the operation of shutoff valve 28, as is obvious. Entry of air under pressure atop the liquid in tanks 16 and 18 will be suitably bafiled, using mufllers or dispersion devices readily obtainable in the market.
  • a very important phase of the present invention resides in the nature of the liquid L employed in the hydraulic system.
  • oil of one type or another was used for driving hydraulic motors, with limited success. Oils possess several undesirable characteristics in this connection, one being that it is capable of carrying air in con siderable quantity which contributes to spongy control resulting in inaccurate motor speeds or lack of uniformity piston advancement. Also, oils will foam if pressured with air, and will release air bubbles resulting in cavitation when orificed, all of which depreciates accuracy of motor operation.
  • the liquid L shall be a hydrous liquid hygroscopic in character, which will entrap little or no air and will permanently absorb and moisture or condensate developed or introduced into the fluid system.
  • Such liquid may be said to be waterbased.
  • One such liquid which has been found satisfactory as the hydraulic fluid L, is glycol or a material of the class of glycol, either undiluted or diluted with water.
  • liquid is one which posses a low surface tension, as compared with the high surface tension of oil materials.
  • Apparatus for moving the impeller element of a fluid motor having a first major port and a second major port through which a liquid may be moved under pressure comprising: a pair of upstandin tanks each having a bottom opening in fluid communication with one of the two major ports of the fluid motor; a quantity of liquid hygroscopic of character and having the qualities of assimilating moisture andcondensate developed in the apparatus to prevent accumulation of free water therein, said liquid filling the motor and standing in stand tanks to the extent of leaving a space above the liquid therein; and means for feeding a gas under pressure alternatively into the space above the liquid in either tank, for displacing liquid from one tank to the other through said motor, thereby to move the impeller.
  • a fluid pipe interconnecting the bottom opening of one tank with said one major port of the fluid motor, said pipe having interposed therein a shut-off valve for alternatively permitting or closing off flow through said pipe; and a shunt pipe intermediate said bottom opening of said one tank and said major port, said shunt pipe ineluding a metering valve operative to control the rate of liquid flow through the shunt pipe and the motor ports when the shut-off valve is in closed position.
  • shutoff valve therein for selectively preventing and permitting flow therethrough.
  • Apparatus for moving the impeller element of a fluid motor having a first major port and a second major port through which a liquid may be moved under pressure comprising: a pair of upstanding tanks each having a bottom opening in fluid communication with one of the two major ports of a fluid motor; a quantity of liquid filling the motor and standing in said tanks to the extent of leaving a space above the liquid therein; means for feeding a gas under pressure alternatively into the space above the liquid in either tank, for displacing liquid from one tank to the other through said motor, a fluid pipe interconnecting the bottom opening of one tank with said one major port of the fluid motor,
  • a shunt pipe intermediate said bottom opening of said one tank and said major port, said shunt pipe ineluding a one-way adjustable metering valve operative to control the rate of liquid flow from said one major part through the shunt pipe, said fluid motor being a hydraulic cylinder having a chamber with a piston therein, and a piston rod projecting from one end of the cylinder through a portion of said chamber, said one major port of the fluid motor aforesaid being influid communication with that portion of the cylinder chamber which contains the piston rod, and said liquid being constituted at least partly of a material of the class of glycol.

Description

April 21, 1970 BECKETT ET AL 3,507,189
AIR-OVER-LIQUID HYDRAULIC SYSTEM Filed May 3, 1968 (VENT) DIRECTION AIR LIQUID [PL LIQUI INVE/V TOR S DONALD E. BECKETT WILLIAM N. BECKETT United States Patent 3,507,189 AIR-OVER-LIQUID HYDRAULIC SYSTEM Donald E. Beckett and William N. Beckett, Wilm ngton,
Ohio, assignors to Beckett-Harcum Company, Wilmington, Ohio, a corporation of Ohio Filed May 3, 1968, Ser. No. 726,310 Int. Cl. F15b 21/04, 11/08, 13/04 U.S. Cl. 914
14 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to an air-over-liquid hydraulic system for enhancing the operation of fluid motors of various types, for example double-acting and S111- gle-acting hydraulic cylinders, rotary motors, and the like.
Common practice has been to actuate fluid motors using oil under pressure, usually metered to or from the motor for controlling the speed thereof. In some applications, the motor speed must be critically regulated and controlled, and very elaborate, complex and expensive valves have been developed and used in the effort to control hydraulic motors with great precision. Better control has been sought also by the use of various types and kinds of oils, and mixtures thereof. Practices other than those mentioned above have been proposed and tried in order to achieve the precision control sought by hydraulic experts, but the problem remains unsolved.
An object of the present invention is to greatly enhance the accuracy of control for hydraulic motors.
Another object of the invention is to provide an improved hydraulic system for the accurate control of fluid motors, which involves simple and inexpensive reliable equipment that requires a minimum amount of care and servicing.
Another object is to provide a hydraulic system possessing the advantages stated, which may be used with safety and great convenience under various conditions of industrial application.
The foregoing and other objects are attained by the means described herein and illustrated upon the accompanying drawing, in which:
The drawing is a diagram of the improved hydraulic system and showing diagrammatically the various components or elements comprising the improved system.
In the drawing, a hydraulic motor is indicated at 4 comprising a cylinder in which is reciprocable a piston 6 having a piston rod 8 extending through one end wall of the cylinder. The piston rod is packed at 10 to avoid leakage of fluid from the cylinder about the rod. The cylinder is provided with major ports 12 and 14 near opposite ends thereof, through which a fluid may be fed to and exhausted from the piston chamber for driving the piston in opposite directions.
For the purposes of the present invention, hydraulic motor 4 may be one of any known type, including single-acting, double-acting, and rotary types of motors. The by way of example in explaining the invention with clarity and simplicity.
At 16 and 18 is disclosed a pair of upstanding tanks or reservoirs adapted to contain a liquid upon which air or another gaseous medium is superposed, the liquid being designated L. At the bottom of tank 16 is a port 20 which by means of a pipe 23 is placed in fluid communication with motor port 12. A port 22 of tank 18 is connected by means of a pipe 24, with the port 26 of a valve 28. A valving member 30 of valve 28 may be shifted to establish either a connection or a shut-off between port 26 and a pipe 32. Pipe 32 connects with the motor port 14.
A shunt pipe 34 may be included in the system to bypass liquid between pipes 34 and 32, Whenever valve 30 is closed. Installed in pipe 34 is a one-way metering valve 36, preferably though not necessarily of the adjustable orifice type, which permits flow of liquid only as the cylinder exhausts through port 14. Accordingly, if pressured liquid is fed into the cylinder through port 12, piston 6 will be moved to displace liquid through port 14 and valve 36 at a predetermined rate of flow. On the other hand, liquid under pressure passing from tank 18 through pipe 24 and valve 30 may pass unrestrictedly to and through motor port 14 to rapid-traverse the piston in the direction of port 12.
It should be understood that the piping and valving system shown is exemplary only, and may be altered to suit the requirements of any given motor control problem. The metering of fluid in both directions through the motor may be accomplished, if desired, by altering the system in accordance with accepted practices in the art, and various other alterations may be resorted to for adapting the system to different applications or problems encountered.
The liquid L fills the motor 4, and partially fills the tanks 16 and 18, so that displacement of liquid from one tank to the other drives the piston 6. To effect such displacement of liquid, air or other gas under pressure may be fed alternatively onto the column of liquid in either tank, through top ports 38 and 40 and pipes 42 and 44. A distribution valve 46 of suitable design is operative to direct air pressure from a source 48 to either of the tanks selectively. When air is fed to one tank for displacing liquid therefrom to operate the motor, the other tank exhauss air from the upper region thereof as will be understoo It should readily be apparent that the liquid L shifts from one tank to the other in a closed system, depending upon manipulation of control valve 46 which may be either manual or automatic. The operation of control valve 46 will be coordinated with the operation of shutoff valve 28, as is obvious. Entry of air under pressure atop the liquid in tanks 16 and 18 will be suitably bafiled, using mufllers or dispersion devices readily obtainable in the market.
A very important phase of the present invention resides in the nature of the liquid L employed in the hydraulic system. In the past, oil of one type or another was used for driving hydraulic motors, with limited success. Oils possess several undesirable characteristics in this connection, one being that it is capable of carrying air in con siderable quantity which contributes to spongy control resulting in inaccurate motor speeds or lack of uniformity piston advancement. Also, oils will foam if pressured with air, and will release air bubbles resulting in cavitation when orificed, all of which depreciates accuracy of motor operation.
In accordance with the present invention, the liquid L shall be a hydrous liquid hygroscopic in character, which will entrap little or no air and will permanently absorb and moisture or condensate developed or introduced into the fluid system. Such liquid may be said to be waterbased. One such liquid which has been found satisfactory as the hydraulic fluid L, is glycol or a material of the class of glycol, either undiluted or diluted with water. The
liquid is one which posses a low surface tension, as compared with the high surface tension of oil materials.
The use of a hydraulic liquid L of the type above mentioned assures great accuracy of motor control, and eliminates the need for complicated and expensive equipment for extracting or preventing the accumulation of air and free Water in the system. The invention contemplates the use of all hydraulic liquids which will perform as stated, to enhance flow control.
What is claimed is:
1. Apparatus for moving the impeller element of a fluid motor having a first major port and a second major port through which a liquid may be moved under pressure, said apparatus comprising: a pair of upstandin tanks each having a bottom opening in fluid communication with one of the two major ports of the fluid motor; a quantity of liquid hygroscopic of character and having the qualities of assimilating moisture andcondensate developed in the apparatus to prevent accumulation of free water therein, said liquid filling the motor and standing in stand tanks to the extent of leaving a space above the liquid therein; and means for feeding a gas under pressure alternatively into the space above the liquid in either tank, for displacing liquid from one tank to the other through said motor, thereby to move the impeller.
2. The apparatus as specified by claim 1, wherein said liquid is a water-base liquid possessing low surface tension properties.
3. The apparatus as specified by claim 1, wherein said liquid is constituted at least partly of glycol.
4. The apparatus as specified by claim 1, wherein said liquid is constituted at least partly of a material of the class of glycol.
5. The apparatus as specified by claim 1, wherein said liquid is a hydrous liquid.
6. The apparatus as specified by claim 1, wherein means is interposed between the bottom opening of one tank and a major port of the motor, for regulating the.
flow of liquid through the ports of the motor.
7. The apparatus as specified by claim 1, wherein is included a fluid pipe interconnecting the bottom opening of one tank with said one major port of the fluid motor, said pipe having interposed therein a shut-off valve for alternatively permitting or closing off flow through said pipe; and a shunt pipe intermediate said bottom opening of said one tank and said major port, said shunt pipe ineluding a metering valve operative to control the rate of liquid flow through the shunt pipe and the motor ports when the shut-off valve is in closed position.
8. The apparatus as specified by claim 7, wherein said metering valve is adjustable as to the flow of liquid therethrough.
9. The apparatus as specified by claim 7, wherein the fluid motor is a hydraulic cylinder having a chamber with.
a piston therein, and a piston rod projecting from one end of the cylinder through a portion of said chamber, said.
12. The apparatus as specified by claim 7, wherein said liquid is constituted at least partly of a material of the class of glycol.
13. Apparatus as specified by claim 1, wherein is included an unimpeded first fluid conduit interconnecting the bottom opening of one tank with said first major port of the fluid motor for free flow of liquid therethrough; a second fluid conduit interconnecting the bottom opening of the other tank with said second major port, said second fluid conduit being divided into two parallel conduit portions intermediate the other tank bottom openin and said second major port, one of said parallel conduit portions having a one-way metering valve therein for metering flow from said second major port to said tank bottom opening and precluding flow therethrough in the reverse direction,
the other of said parallel conduit portions having a shutoff valve therein for selectively preventing and permitting flow therethrough.
14. Apparatus for moving the impeller element of a fluid motor having a first major port and a second major port through which a liquid may be moved under pressure, said apparatus comprising: a pair of upstanding tanks each having a bottom opening in fluid communication with one of the two major ports of a fluid motor; a quantity of liquid filling the motor and standing in said tanks to the extent of leaving a space above the liquid therein; means for feeding a gas under pressure alternatively into the space above the liquid in either tank, for displacing liquid from one tank to the other through said motor, a fluid pipe interconnecting the bottom opening of one tank with said one major port of the fluid motor,
said pipe having interposed therein a shut-01f valve for.
alternatively permitting or closing off flow through said pipe; and a shunt pipe intermediate said bottom opening of said one tank and said major port, said shunt pipe ineluding a one-way adjustable metering valve operative to control the rate of liquid flow from said one major part through the shunt pipe, said fluid motor being a hydraulic cylinder having a chamber with a piston therein, and a piston rod projecting from one end of the cylinder through a portion of said chamber, said one major port of the fluid motor aforesaid being influid communication with that portion of the cylinder chamber which contains the piston rod, and said liquid being constituted at least partly of a material of the class of glycol.
References Cited UNITED STATES PATENTS OTHER REFERENCES Hydraulic Handbook, 2nd edition, published by Trade and Technical Press, Limited, Marden, Surrey, England,
1960; pp. 211 to 221; T1 840, H 97, 1960 C3. PAUL E. MASLOUSKY, Primary Examiner US. (:1. X.R. 91-466; 92-142
US726310A 1968-05-03 1968-05-03 Air-over-liquid hydraulic system Expired - Lifetime US3507189A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US72631068A 1968-05-03 1968-05-03

Publications (1)

Publication Number Publication Date
US3507189A true US3507189A (en) 1970-04-21

Family

ID=24918074

Family Applications (1)

Application Number Title Priority Date Filing Date
US726310A Expired - Lifetime US3507189A (en) 1968-05-03 1968-05-03 Air-over-liquid hydraulic system

Country Status (1)

Country Link
US (1) US3507189A (en)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4015538A (en) * 1975-05-27 1977-04-05 Swift And Company Limited Carcass transfer method and device
US4110981A (en) * 1977-08-17 1978-09-05 Murphy John R Hydraulic motor with air distributor-operated valves
US4149384A (en) * 1974-08-01 1979-04-17 Marshall Don J Fluid pressure amplifier
US4223531A (en) * 1978-04-03 1980-09-23 Kobe Steel, Limited Gas pressure to hydraulic pressure converter system in an oil pressure actuator
US4268007A (en) * 1976-07-22 1981-05-19 Chittenden Jeremy B Valve actuating equipment
FR2490511A1 (en) * 1980-09-22 1982-03-26 Berry Arnold DEVICE FOR PRINTING A SHIFT MOVEMENT TO A PROJECTION CANON
US4827672A (en) * 1987-04-27 1989-05-09 Buehler Ltd. Abrasive cutting wheel system
EP0399102A1 (en) * 1989-05-15 1990-11-28 Ishigame Machinery Co., Ltd. Hydraulic-pneumatic cylinder device
US20100300712A1 (en) * 2009-05-26 2010-12-02 Potter Jay E Hydraulic-Pneumatic Third Point Connector
US20160238042A1 (en) * 2015-02-17 2016-08-18 Eurocharm Holding Co., Ltd. Driving Device Using Pneumatic-Hydraulic Pressure as a Power Source for a Vehicle

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2674138A (en) * 1952-04-30 1954-04-06 Paul D Mize Drilling, boring, or other machine
US2916017A (en) * 1957-10-17 1959-12-08 Crossley Machine Company Inc Feed control for machine tools
US3122989A (en) * 1964-03-03 Continuous manufacture of sausage
US3124371A (en) * 1964-03-10 Trailer steering control

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3122989A (en) * 1964-03-03 Continuous manufacture of sausage
US3124371A (en) * 1964-03-10 Trailer steering control
US2674138A (en) * 1952-04-30 1954-04-06 Paul D Mize Drilling, boring, or other machine
US2916017A (en) * 1957-10-17 1959-12-08 Crossley Machine Company Inc Feed control for machine tools

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4149384A (en) * 1974-08-01 1979-04-17 Marshall Don J Fluid pressure amplifier
US4015538A (en) * 1975-05-27 1977-04-05 Swift And Company Limited Carcass transfer method and device
US4268007A (en) * 1976-07-22 1981-05-19 Chittenden Jeremy B Valve actuating equipment
US4110981A (en) * 1977-08-17 1978-09-05 Murphy John R Hydraulic motor with air distributor-operated valves
US4223531A (en) * 1978-04-03 1980-09-23 Kobe Steel, Limited Gas pressure to hydraulic pressure converter system in an oil pressure actuator
FR2490511A1 (en) * 1980-09-22 1982-03-26 Berry Arnold DEVICE FOR PRINTING A SHIFT MOVEMENT TO A PROJECTION CANON
US4827672A (en) * 1987-04-27 1989-05-09 Buehler Ltd. Abrasive cutting wheel system
EP0399102A1 (en) * 1989-05-15 1990-11-28 Ishigame Machinery Co., Ltd. Hydraulic-pneumatic cylinder device
US5042253A (en) * 1989-05-15 1991-08-27 Ishigame Machinery Co., Ltd. Hydraulic-pneumatic cylinder device with annular flexible bag as interface
US20100300712A1 (en) * 2009-05-26 2010-12-02 Potter Jay E Hydraulic-Pneumatic Third Point Connector
US8464802B2 (en) * 2009-05-26 2013-06-18 Tri Trac Innovations, Inc. Hydraulic-pneumatic third point connector
US20160238042A1 (en) * 2015-02-17 2016-08-18 Eurocharm Holding Co., Ltd. Driving Device Using Pneumatic-Hydraulic Pressure as a Power Source for a Vehicle

Similar Documents

Publication Publication Date Title
US3507189A (en) Air-over-liquid hydraulic system
US2697446A (en) Filling nozzle assembly
US2858767A (en) Pumping apparatus
GB1045764A (en) Valve means for controlling operation of a fluid motor
NZ504740A (en) Flow control valve for filling tanks from pressurised supply, with shut-off caused by float valve in tank, interconnected by bleed line from valve
US2490823A (en) Hydraulic-pneumatic system
US2443146A (en) Apparatus for flowing viscous liquids, including a by-pass between a pump outlet andthe liquid chamber
US4305531A (en) Pneumatically operated controlled volume dispensing device
US3005444A (en) Control means for fluid actuated work cylinders
US2130611A (en) Valve
US2603192A (en) Hydraulic valve for controlling the flow of fluid to cylinders
US2001988A (en) Control mechanism
US720492A (en) Device for filling cans.
US2943765A (en) Container mounted fluid pressure displacement pump
US3456297A (en) Hydraulic mould locking devices
US3279376A (en) Proportioning apparatus
GB981782A (en) Fluid pressure relief valve
US3334547A (en) Hydraulically operated oscillator control apparatus
US3053050A (en) Device for the lifting of loads
US1586770A (en) Vending apparatus for liquids
GB1332579A (en) Device for holding a control valve in an end position
CH609587A5 (en) Device for delivering liquid from a container
US2675785A (en) Power hydraulic remote-control
US3223114A (en) Automatic shut-off for pipeline
US3150857A (en) Fluid dump valve